Example embodiments relate to transistors and methods of manufacturing the same. More particularly, example embodiments relate to highly integrated complementary metal-oxide-semiconductor (CMOS) transistors showing a high performance and methods of manufacturing the same.
Various researches on forming highly integrated transistors having a high performance have been conducted.
For example, a stress controlling process for applying stress onto a channel region of a transistor has been studied. In addition, researches on various materials forming a gate insulating layer and a gate electrode of a transistor also have been widely conducted. Materials having a high dielectricity have been used for forming the gate insulating layer instead of a silicon oxide layer and metal compounds have replaced polysilicon for forming the gate electrode. Further, alternative materials of a substrate for forming the transistor also have been studied.
However, since an n-type metal-oxide-semiconductor (NMOS) transistor and a p-type metal-oxide-semiconductor (PMOS) formed on one substrate may have different electric characteristics, formations of the NMOS transistor and the PMOS transistor through the same manufacturing process may not be an easy task. In addition, physical properties of each material for forming each element of the NMOS and the PMOS transistors may be different and the physical properties of the materials constituting the elements may have a trade-off relationship. Therefore, an optimized NMOS transistor and PMOS transistors may be formed through a complicated manufacturing process.